Small guns are powerful because they include shotguns, submachine guns, and rifles. You do want high Perception. Once you get your guns skill up, you can reliably hit burst and aimed shots. Blinding enemies makes them permanently helpless, so go for the eyes. The Better Criticals perk gives a chance for criticals to kill instantly. Later in the game you can use the Tag! perk to quickly level up energy weapons to use against heavy armor. It's helpful, but not strictly necessary because while your regular attacks will barely scratch them, your criticals will still disable or kill.